feat(gatsby-graphiql-explorer): lower minimum node version (#38577)

feat(gatsby-graphiql-explorer): lower minimun node version

Author: pieh

packages/gatsby-graphiql-explorer/package.json

@@ -59,6 +59,6 @@
     "webpack-cli": "^5.1.4"
   },
   "engines": {
-    "node": ">=18.0.0"
+    "node": ">=14.15.0"
   }
 }